(19) It is a covenant of salt.--i.e., an indissoluble covenant. (See Leviticus 2:13, and Note; also 2Chronicles 13:5.) Hence the phrases used by the Greeks to denote the breach of a covenant, "Where is the salt?" and "They overstepped the salt." (Comp. Pliny, H. N., xxxi. 41; Cic., De Div., ii. 16; Virgil, Ecl., viii. 82.)

Verse 19. - All the heave offerings of the holy things. Those, viz., enumerated from verse 9. It is a covenant of salt for ever. Septuagint, διαθήκη ἀλὸς αἰωνίου (cf. 2 Chronicles 13:5). Salt was the natural emblem of that which is incorruptible; wherefore a binding alliance was (and still is) made by eating bread and salt together, and salt was always added to the sacrifices of the Lord (Leviticus 2:13; Mark 9:49).

18:8-19 All believers are spiritual priests, and God has promised to take care of them. Godliness has the promise of the life that now is. And from the provision here made for the priests, the apostle shows that it is the duty of christian churches to maintain their ministers. Scandalous maintenance makes scandalous ministers. The priests were to be wholly devoted to their ministry, not diverted from it, or disturbed in it, by worldly care or business. Also, that they might be examples of living by faith, not only in God's providence, but in his ordinances. The best should be offered for the first-fruits unto the Lord. Those who think to save, by putting God off with the refuse, deceive themselves, for God is not mocked.All the heave offerings of the holy things,.... All before mentioned, and whatsoever comes under that name:

which the children of Israel offer unto the Lord; either by his commandment, or of their own freewill:

have I given thee, and thy sons, and thy daughters with thee, by a statute for ever: so providing for their maintenance by an irrepealable law as long as their priesthood lasted, even until the Messiah should come:

it is a covenant of salt for ever before the Lord unto thee, and thy seed with thee: an incorruptible, inviolable, durable covenant, which should last for ever, even until the Gospel dispensation or world to come should take place; and it would remain ever before the Lord in his sight, who would take care it should never be made void, but stand fast with Aaron and his posterity as long as his priesthood endured.